{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T12:04:55Z","timestamp":1790683495914,"version":"4.1.0"},"reference-count":35,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2019,7,24]],"date-time":"2019-07-24T00:00:00Z","timestamp":1563926400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>Compounds were isolated from Ecklonia stolonifera Okamura, a marine brown alga widely consumed as food. Among the isolated compounds, 974-A was demonstrated for the first time to be a potent competitive inhibitor of mushroom tyrosinase activity towards l-tyrosine and l-DOPA (IC50 values = 1.57 \u00b1 0.08 and 3.56 \u00b1 0.22 \u00b5M, respectively). Molecular docking simulations clarified that the hydroxyl residues of the isolated compounds formed hydrogen bonds with residues at the catalytic and allosteric sites of tyrosinase, while other residues participated in hydrophobic interactions. Moreover, 974-A, phlorofucofuroeckol-A and eckol reduced the cellular melanin content and tyrosinase activity, and downregulated the expression of melanogenesis enzymes including tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 in B16F10 melanoma cells. These compounds also effectively scavenged radicals at the cellular level. Thus, our results revealed that compounds isolated from E. stolonifera are potent tyrosinase inhibitors with potential applications in the cosmetic industry for treatment of hyperpigmentation and for the anti-browning effect in the agricultural field.<\/jats:p>","DOI":"10.3390\/antiox8080240","type":"journal-article","created":{"date-parts":[[2019,7,24]],"date-time":"2019-07-24T10:48:19Z","timestamp":1563965299000},"page":"240","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":87,"title":["Phlorotannins with Potential Anti-Tyrosinase and Antioxidant Activity Isolated from the Marine Seaweed Ecklonia stolonifera"],"prefix":"10.3390","volume":"8","author":[{"given":"Bandana","family":"Manandhar","sequence":"first","affiliation":[{"name":"Department of Food and Life Science, Pukyong National University, Busan 48513, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9112-1630","authenticated-orcid":false,"given":"Aditi","family":"Wagle","sequence":"additional","affiliation":[{"name":"Department of Food and Life Science, Pukyong National University, Busan 48513, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2683-7373","authenticated-orcid":false,"given":"Su Hui","family":"Seong","sequence":"additional","affiliation":[{"name":"Department of Food and Life Science, Pukyong National University, Busan 48513, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8482-1129","authenticated-orcid":false,"given":"Pradeep","family":"Paudel","sequence":"additional","affiliation":[{"name":"Department of Food and Life Science, Pukyong National University, Busan 48513, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyeung-Rak","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Food and Life Science, Pukyong National University, Busan 48513, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyun Ah","family":"Jung","sequence":"additional","affiliation":[{"name":"Department of Food Science and Human Nutrition, Chonbuk National University, Jeonju 54896, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9034-8868","authenticated-orcid":false,"given":"Jae Sue","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Food and Life Science, Pukyong National University, Busan 48513, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,7,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1111\/j.1600-0749.2006.00358.x","article-title":"Regulation of human skin pigmentation and responses to ultraviolet radiation","volume":"20","author":"Miyamura","year":"2007","journal-title":"Pigment Cell Melanoma Res."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"14821","DOI":"10.1074\/jbc.M111497200","article-title":"Abnormal acidification of melanoma cells induces tyrosinase retention in the early secretory pathway","volume":"277","author":"Halaban","year":"2002","journal-title":"J. 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